Capsules take too long to dissolve.
Cayenne tincture. Drops applied under the tongue. Absorbs instantly. No time is wasted.
I have heard to directly place cayenne pepper under the tongue in case of heart attack, not capsules. You would have to open the capsules.
On another vein, cayenne capsules do help some forms of arthritis to reverse. It cleared up my hands over a period of time. However if you a hiatial hernia, (malfunctioning lower stomach valve), capsules on an empty stomach can give you hellatious heart burn.